High Quality Content by WIKIPEDIA articles! Founded in 1899, Gallatin National Forest is located in south central Montana, United States. The forest comprises 2.1 million acres (8,500 km²) and has portions of both the Absaroka-Beartooth and Lee Metcalf Wilderness areas within its boundaries. Gallatin National Forest borders Yellowstone National Park on the north and northwest and is part of the Greater Yellowstone Ecosystem, a region which encompasses almost 20000000 acres (81000 km2). The forest is named after Albert Gallatin (1761-1849), U.S. Secretary of the Treasury and scholar of Native American languages and cultures.